Since 1982, the Bird Observatory and its volunteers have been monitoring local populations of herons, egrets, terns, and gulls that rely on the San Francisco Bay as breeding grounds. Information on colony sizes allows us to document population trends, inform resource management decisions, and contribute to other projects including the "Annotated Atlas and Implications for the Conservation of Heron and Egret Nesting Colonies in the San Francisco Bay Area", a collaboration between SFBBO and Audubon Canyon Ranch. The Colonial Waterbird Monitoring Project also records data on timing of nesting and evidence of predation.